RxNES is basically 80 lines of code added to an Open Source NES Emulator within the Unity3D Engine. Unity3D is not required, you can upgrade games with the Standalone Build.

RxNES v1.495 Changelog:

- Added : GUI Recording Toggle/Button, near Top-Right Screen Corner.
- The Below have been improved upon in this version.
- Added Game-Play Recording & Playback, with Fast-Forward and Rewind!
(Uses "Tile Collection" so you can record yourself playing now, and watch again with new custom tiles later!!
[Doesn't record while paused! :) ].
Recodings now record / play forever unlimited minutes. 50 MB / Min.
No Sound in recordings, will be added soon. (This will increase the file size obviously.)